To manufacture and use prefabricated panels in building systems is today well known. The panels may be provided to form walls, roof, or floor of a building to be constructed, and may thus be provided with different materials and structures in order to fit their purpose. In order to improve the building techniques different solutions have been proposed in the literature.
EP-A-462,790 discloses a building system which comprises rooms formed from prefabricated room units, wherein the units include walls and a ceiling. The room units are arranged in rows where each row has adjacent pairs of room units and where each pair of units is structural mirror images of each other. Even though the elements are prefabricated, there is still a lot of work to be done with the interior before the building may be ready to use as e.g. a hotel. The work at the construction site is time-consuming and expensive since many workers must be hired to finish the interiors.
Hence, this known system involves a high cost which probably is the main reason why it has not been put into practice.
An even earlier example of prefabricated elements for building structures is disclosed in GB-A-1,213,009.
US-A-2005/0108957 discloses a prefabricated module which is intended to be used in a multi-storey building. The modules may contain a bathroom, a kitchen, a staircase or a combination of the previous mentioned and may be stacked on top of each other and then installed concurrently with the surrounding structure. One module may be configured to have a dual room layout which means that the module will include e.g. two bathrooms which are a mirror image of each other. Additionally, each module has a vertical shaft which includes features like water supply, waste sewage and ventilation shaft. This known system is complicated and suffers from the same problem as the costly system described above.
As to background art, WO-A-2006/136853 could be mentioned as well since it discloses a prefabricated service pod. However, this publication does not suggest low-cost prefabrication based on non-complex structures. Hence, the proposed service pods are not suitable for building projects of the type today's market demands.
Prefabricated elements for buildings do not only include service pods and the like, but also various types of wall and panel elements. An example of such an element is disclosed in EP-A-565,842. However, this known element only constitutes a part of a building and the publication does not suggest any overall solution to the problem of how to construct an entire building which meets today's requirements of low-cost construction projects to be performed under time pressure.
WO-A-2005/093185 describes a modular building system which comprises a set of panels wherein the panel may be a wall panel, a window panel or a door panel. Each panel has a wooden framework with a skin, wherein the size of the panels may be adjusted so to fulfill the purpose of the panel. A disadvantage with these panels is that they are all custom made which means that the production of the panels must be very flexible and manage a quick adjustment to manage to build a multi-storey building within a short period of time. More adjustments and part projects within the overall project cost money, are time consuming and could lead to more mistakes which will be revealed once the panels are on the building site. These known panels may be delivered open, which means that the insulation and one skin are missing. This will result in more work on site and a need for more workers.
In view of the above-mentioned disclosures, there is a need for an improved solution for building systems based on prefabricated elements.